The design and optimization efforts of electrical/electronic magnetic structures such as transformers often involve adjusting the dimensions of the magnetic core. Depending on the application, the requirements for dimensions and volume of the structure can differ. For example, a device that needs to handle 1 kW of power will be significantly greater in size than a device made of the same material but only needs to handle 1 W of power.
A commonly used design parameter is the WaAc product, which determines the device's power-handling capability. Wa is referred to as the window area, and Ac is referred to as the core area. When designing a magnetic core, the designer typically starts with a specification of the WaAc product and chooses a core structure that meets the specification. Many conventional core structures, however, are sub-optimal in terms of their magnetic volume utilization and can lead to excess core loss.